- published: 07 Sep 2013
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In vascular plants, the root is the organ of a plant that typically lies below the surface of the soil. This is not always the case, however, since a root can also be aerial (growing above the ground) or aerating (growing up above the ground or especially above water). Furthermore, a stem normally occurring below ground is not exceptional either (see rhizome). So, it is better to define root as a part of a plant body that bears no leaves, and therefore also lacks nodes. There are also important internal structural differences between stems and roots.
The first root that comes from a plant is called the radicle. The four major functions of roots are 1) absorption of water and inorganic nutrients, 2) anchoring of the plant body to the ground, and supporting it, 3) storage of food and nutrients, 4) vegetative reproduction. In response to the concentration of nutrients, roots also synthesise cytokinin, which acts as a signal as to how fast the shoots can grow. Roots often function in storage of food and nutrients. The roots of most vascular plant species enter into symbiosis with certain fungi to form mycorrhizas, and a large range of other organisms including bacteria also closely associate with roots.
A boy is a young male human, usually child or adolescent. When he becomes an adult he's described as a man. The most apparent thing that differentiates a boy from a girl is that a boy typically has a penis while girls do not. However some intersex children with ambiguous genitals, and biologically female transgender children, may also be classified or self-identify as a "boy".
The term "boy" is primarily used to indicate biological sex distinctions, cultural gender role distinctions or both. The latter most commonly applies to adult men, either considered in some way immature or inferior, in a position associated with aspects of boyhood, or even without such boyish connotation as age-indiscriminate synonym. The term can be joined with a variety of other words to form these gender-related labels as compound words.
The word "boy" comes from Middle English boi, boye ("boy, servant"), related to other Germanic words for boy, namely East Frisian boi ("boy, young man") and West Frisian boai ("boy"). Though the exact etymology is obscure, the English and Frisian forms probably derive from an earlier Anglo-Frisian *bō-ja ("little brother"), a diminutive of the Germanic root *bō- ("brother, male relation"), from Proto-Indo-European *bhā-, *bhāt- ("father, brother"). The root is also found in Flemish boe ("brother"), Norwegian dialectal boa ("brother"), and, through a reduplicated variant *bō-bō-, in Old Norse bófi, Dutch boef "(criminal) knave, rogue", German Bube ("knave, rogue, boy"). Furthermore, the word may be related to Bōia, an Anglo-Saxon personal name.
Portable Document Format (PDF) is a file format used to represent documents in a manner independent of application software, hardware, and operating systems. Each PDF file encapsulates a complete description of a fixed-layout flat document, including the text, fonts, graphics, and other information needed to display it. In 1991, Adobe Systems co-founder John Warnock outlined a system called "Camelot" that evolved into PDF.
While the PDF specification has been available free of charge since at least 2001, PDF was originally a proprietary format controlled by Adobe. It was officially released as an open standard on July 1, 2008, and published by the International Organization for Standardization as ISO 32000-1:2008. In 2008, Adobe published a Public Patent License to ISO 32000-1 granting royalty-free rights for all patents owned by Adobe that are necessary to make, use, sell and distribute PDF compliant implementations.
PDF's adoption in the early days of the format's history was slow.Adobe Acrobat, Adobe's suite for reading and creating PDF files, was not freely available; early versions of PDF had no support for external hyperlinks, reducing its usefulness on the Internet; the larger size of a PDF document compared to plain text required longer download times over the slower modems common at the time; and rendering PDF files was slow on the less powerful machines of the day. Additionally, there were competing formats such as DjVu (still developing), Envoy, Common Ground Digital Paper, Farallon Replica and even Adobe's own PostScript format (.ps); in those early years, PDF was popular mainly in desktop publishing workflows.